Removal of a bad odor emitted in a living environment has been one of the great subjects in pursuit of comfort. It is known that bad odors can be removed or destroyed through various mechanisms, such as masking, adsorption, neutralization, and the like, and a wide variety of deodorizers or deodorants utilizing these mechanisms are now on the general market.
On the other hand, thermoplastic resin products have now thoroughly penetrated into our daily life and been widely used. Therefore, the thermoplastic resin molded products are broadly employed as containers for the deodorizers. However, thermoplastic resin products having deodorizing properties in themselves are rarely known.
Deodorizers are classified by deodorizing mechanism into two large groups, one by adsorption and the another by chemical reaction. The reactive deodorizers produce rapid and powerful effects on some specific sources of bad odors. For example, it is known that ferrous sulfate can remove ammonia and the reaction product between ferrous sulfate and ammonia is capable of removing ammonia and hydrogen sulfide, respectively, as disclosed in Japanese Patent Publication No. 6698/55 and Japanese Patent Application (OPI) No. 50889/76 (the term "OPI" as herein used means "unexamined published application"). The deodorizing mechanism by these compounds is admittedly assumed to follow the following reactions: EQU FeSO.sub.4.7H.sub.2 O+2NH.sub.3 .fwdarw.(NH.sub.4).sub.2 SO.sub.4 +Fe(OH).sub.2 +5H.sub.2 O EQU Fe(OH).sub.2 +H.sub.2 S.fwdarw.FeS+2H.sub.2 O
It has been recognized by recent studies that these deodorizers can exert their deodorizing performance through the above-described mechanism even when blended with thermoplastic resins.
However, divalent iron compounds tend to be gradually oxidized under ambient conditions to form an iron rust smell and iron rust-colored stain which contaminate materials in contact therewith. It is also known to use ascorbic acid in combination for the purpose of stabilizing the divalent iron compounds, but ascorbic acid cannot be expected to show its effects after molding because it is generally decomposed at molding temperatures of thermoplastic resins.